Process of making soap



Aug. 24, 1943. B. CLAYTON 2,327,502

PROCESS 0F MAKING soAP Filed Dec. 26, 1940 NEU TRHLI ZED UIL NEU TRHL IZED GIL Patented Aug. 24, 1943 *.Plioolissfor mais@ soar .Bernier-ein. Clayton,` Houston, Terr., assigner t0 Rening, Inc., Reno,

Nevada -Nev., anoeri'poration of Application December 2E?, 1942 Serial No. 371,811 if Claims.V (Cl. Z50-QMS) The'present` invention relates to a process 0f rening animal andvegetableoils and vto a process of making soap,k the latter utilizing the soap stoekobtained from the oil refining process.

In certain glyceride oil refiningv processes 4a considerable excess ofv alkali over that required to neutralize the ireefatty acids `and to remove other impurities, is employed. Vlhen. the neu- Y tralized fatty acids,4 together with the excessalkali,u Water and other impuritiesere separated from the refined oil, the separated .material is found to contain alarge excess of alkali. For example, in my priorfatent2,190,594,11 Vhave described a process for refining glycerideoils in which soda ash in the proportion of fromv three to twelve times the amount required to neutralize the free fattyaeids mayv be employed. The separated soap stock from such approcess contains a lange excessv of alkali. -The present invention contemplates tlie use of tlfiisnsoap` stock with its excess alkali saponifying agent for the .prof duction ofvsvoap. zThe `alkali-soap stockrnixture maybe added to aouantityxof either free fatty acids, glyceridesJ or othersaponiiiable ,material and the same run through a soap making process. lin thsmanner itis possibleto makefuse of( alow cost material as the saponifyingagent.

' crude glyeenoeoos consist chiefly of fatty acid glycerides land contain minor propfnjtions of lirnpuritiessucnas lfatty acids, gums, phosphatides, coloring matter andthe-like. tne preparation of edible oils itlisusually desired tomremove the major proportion of these impurities. However this may beclone in a number Iof-vvays. Bor example, .the crude oilcontaining allthe-impurities may be directly subjected to an alkali reiniging operation which removes thefmajorproportion of all these impurities. n Ityvill be apparentfthat the soap stocker foots `resulting `-irom such a refining operation Wouldcontain lin addition A.to the soap resulting from vthe neutralization A.of the free fatty acids, `thev gums, ypliospl-iatides, co1- oring matter and other-impurities. This soap stock may be employedin Vthe present process where a high quality soap is not the primary consideration. `It will .be apparent that soap made from this soap vstock .by ordinary .batch processes will contain various ,quantities of the impuritiespresent in the lsoap stock. It is extremely diicult to remove certain Aof such impurities from a soap made from the soap stock.

In refining operations it issometinies desirable to subject the oil to a degumrning operation prior to the alkali reiining. @ich an operation may consist of mixing the crude oil with renou .quam i5 titiespf Water or electrolytes such as weak'solutionsof boric acid and the like, which serve to precipitate the gums and phosphatides following which the precipitated impurities may be separated from theloil. In general solutions of Weak acids or alkalies such as alkali metal salts or extremely 4dilutetsolutions of strong Ialkaliesor acidsare suitable. The separated oil may then be subjectedl tO-.an alkali rening operation and ity/ill be evident that the soap stock resulting from such a refining.operationvlillbe free from many ofi-the impurities encountered in a soap stock resulting from the refining oi crude oil'. Aoeordinglyrwhen such a relatively pure soap stock isl employed ias the saponifying `agent', according tothe present Vinvention the final soap resulting Will be of a higngracle. Y l

instill other refining operations the free fatty acids may beneutraiizedby mea-ns, of an valkali andnrnay'be separated from the oil, the quantity of alkaliiemployed being intendedprimarilyffor the removal of freeifattyiacids. ySucnanoil maythenhe subjectedtoa `second `alkali treatment for the removal 'of color.` :It willbe apparent ltliatthe soap stock resulting from such an `operation Willbeurelativelyefree of color mpurities. nccordinglmwheresuch avsoap stock is employed as tnesaponifyingagent according to the present invention the iinal soap resulting will befrelatively free trom colorimpurities.

y vllierethe purest product is desired,:the soap stock resulting l from p a Apreliminarily degummed oil, and which isree from colorimpurities'may be. employed, as'the saponifying agent inthepresent process. However, -Aat-the high'temperatures contemplatedfin the preferred process of the present invention, many ofthe impurities above referred `,to lare lpreken `down into volatile compounds, ywhclrmay'beremoved fromthe soapby vaporization, thus permitting a relatively high grade soap tobe produced even when a soap stock containing relatively large amounts of impurities isemployed. Thus bythe employment of my Clehydration and deodorization process as described in my copending application Serial No. 318,753, filed February 13, 1940,.,now Patent No. 2,230,196 granted January 28, lli, of Which this case is a continuation-ln-.pa-rt,'itV is possible to produce a relatively pure soap when using a relatively impure soap stock as the saponifying agent.

It is therefore the primary object of the pres# ent-invention vto provide a process for .the production of soap utilizing as the saponifying agent the alkali-,soap stock rnixture resulting from the alkalirefiningof a glyoeride oil. A i

It is another object of the present invention to provide a process utilizing the alkali-soap stock mixture resulting from the refining of a preliminarily degummed oil as a saponifying agent.

It is a further object of the present invention to employ in a soap making process a waste alkali Solution resulting from the alkali rening of a glyceride oil.

These and other objects will be apparent from the following description of the process and the drawing in which:

Figure l is a diagrammatic sketch of an apparatus suitable for carrying out the process of the present invention; and

Figure 2 is a diagrammatic fragmentary sketch of an apparatus which may be employed to carry out a modied process:

Referring more particularly to Figure l, IG indicates a tank as a source of supply for the oil to be refined. The tank Ii? may be provided with a hea-tinCf coil Il tobring the oil to a predeterined temperature at which the oil is flowable. A tank I2 may contain neutralizing agent and may be provided'with a heating coil I3 to heat the neutralizing agent to a desired temperature for mixing with the oil. A stream of oil may be withdrawn from the tank I!) byk a pump I4 and delivered through a heat exchangev device I5 to a ilow mixing device I6. The heat exchange device I5 preferably includes a coil Il through which the oil is passed, which coil is positioned in a casing Iii through which any desired heating medium may be circulated. Neutralizing agent may be withdrawn from the tank I2 by a pump I 3 and delivered to the ow mixer I 5. The pumps I4 and I9 are `preferably arranged to deliver accurately proportioned streams of oil and neutralizing agent respectively to the mixer I6, and one way of accomplishing this is to drive the pumps Iii and IS from a variable speed'electric motor 2i), with a variable speed device 2i positioned between the motor and the pump I9. The ow mixing device may be of any suitable type capable of repeatedly forming a thorough mixture of c-il and reagent. The mixing device disclosed in Patent No. 2,142,062 is preferred, but another device such as a closed mechanical agitator or a colloid mill may be employed if desired. I

The oil and reagent are preferably mixed under pressure and out of contact with the atmosphere? The resulting mixture may be passed through a heat exchange device 22 similar to heat exchange device I5 and delivered to the continuous centrifugal separator 23.

The refined oil is withdrawn at 24 While the soap stock is discharged at 25 into a mixing tank 35. VSaponiable matter such as free fatty acids, glycerides, and the like, may be preheated by coil 2'! located in supply tank 28 and from there discharged into the mixing tank 2B through conduitY 2a. Mixing tank 26 may be provided with an agitator Si) driven by motor 3|. The saponiable matter and the soap stock containing the excess alkali may be intimately mixed in the tank 25. Preferably the agitation is continuous so that a mixture of vuniform composition may be continuously Withdrawn from the bottom of tank 25. The tank 26 may be Vclosed from the atmosphere where conditions, such as the temperature of the saponiable'matter or soap stock, make contact with the-atmosphere undesirable.

Pump 32 may be employed to Withdraw a stream of the mixture from tank 26 through con- CII CII

duit 33 and force the same under pressure into heating coil 34 located within heating chamber 35. A suitable burner 36 may be employed utilizing gas or other combustible material as the heating medium. The mixture of soap stock, alkali and saponifiable matter is heated during passage through the coil 34 and the reaction may be substantially completed within the coil. It is preferred to supply sufficient additional heat to the mixture in the coil or coils so that when the reacted mixture is discharged from the coil into a lower pressure chamber the heat within the mixture will be sufficient to effect vaporization of the contained impurities. The reacted mixture is withdrawn from the coil through conduit 31 and is preferably discharged into a vaporizing chamber 38 similar to that disclosed in my prior Patent 2,218,279. This vaporizing chamber is composed of an inner chamber 39 around which is disposed the outer jacket 40. The space 4I between the inner and outer jackets may be employed to regulate the temperature of the inner chamber by means ol a suitable heat cxchan ge medium. Suitable inlet and outlet passages 42 and may be employed for this purpose. Steam maybe introduced into the chamber if desired, through the conduit 44. The chamber terminates at the bottom in a conical shaped member which is'Y adapted to discharge the contents of the chamber into a screw conveyor d5, by means of which the contents of the chamber may be discharged to atmosphere without permitting atmospheric gases to enter the chamber. The screw conveyor 45 is preferably jacketed as at @5 so that a cooling medium may be circulated around the screw conveyor thus enabling the soap mixture being discharged from the chamber to be reduced in temperature so that it will form a vacuum seal for the chamber and not be deleteriously affected by Contact with the atmosphere. The mixture in conduit 31 may be discharged into the chamber by means of nozzles 47 which direct the sprayed material down along the inner walls of the chamber. While it is preferred Vto complete saponication in coil 3d, saponiication may be completed in tank Qdby means of the latent heat of the reactants or by means of additional heat supplied therein. Likewise, a separate saponication coil such as employed in my Patent No. 2,178,987 may be used. In these cases, coil may be employed primarily to supply heat for the vaporization of impurities. l

Upon introduction to the vaporizing chamber the pressure on the saponied mixture may be reduced. 'The latent heat within the mixture may be suiiicicnt to vaporize glycerine, if a glyceride oil was employed, water and other impurities. These vapors may be withdrawn through conduit 48 and passed into a suitable vapor se arating chamber fit1.VV Any unvaporized material may be returned to the vaporizing chamber by means of conduit 5i). The vapors from the vapor separating chamber may be passed through suitable fractional condensers 5I 52 and 53 where individual constituents, such as glycerine, water, and other impurities may be separated from cnc another if desired. Fump4 54 may be employed to maintain the chamber and the condenser systems under vacuum.

In thepreierred process suiiicient ash solution of proper concentration to provide effective separation is admixed in iiow with the oil in a single mixing operation in accordance lwith Figure 1. The concentration of the aqueous YYsowere@ fatt een 'si toeneet'thegeaaiea, but it is ere erred Y y aanaefeapityedasitii to heat the "mixture `underV pressure to""a"`fairly high temperature in order to produce a uid iixture and so that the 'resultingfniixture contain `sufficient' heat to vaporiaethe Jimpurities thereinL when the mixturelis dichar'ged lower pressure 'chamber' for ya temperatures 'in the 'coil will 'rang mately 250?. 'to' 600 'F."d'epen ture of the soap stock, saporiiabl r quality of soap desired' It'is'po'ssible, toa-dd additional heatto the'"spraye'd`v the vaporizing chamb'erby means of change jacket V'surrou'ndingftlie means of the pipe through which superheat'e'd steam may be introduced. Where glyceride oilisthe saponiiable material employed higher temperatures areii'sualily sirable to expedite `the'sar' oniiication' of the" neutral oil, Accordingly higher` temperatures and ie heat 'ex'- higher pressures'rnay be employedWithin"coilll'iL i V In some cases itis desirable toaddo the Scan stock'in tank Z6 more Vsaponiiiablerinaterial than .y

the excess alkaliin thesoap stocklivi'll saponify.

In this" case vadditional alkalipreferably in the form of a caustic soda solution may :begintrodu'ced lQ the mixture. is particularly desirable where the soda ash solution employed in 'reflning was of a high concentration, thusresulting in avery viscous soap stock: The Water, contained in the caustic soda solution added to the mixture SeiYS. ,ilo dilute the mixture @ne more e'sil'il ,fier/able Where desired it is that ex ,e mixture Sumeiently newbie. 'The C'iiiiic re@ 'added alSQ is ici 'yaliie when 'elyceri'de oilsare the Se i? steek 'terrains substantial quantities of en rapped glyoeride o il, since the caustic soda is'rnore effectiye in saponiiying the neutral glyceride oil than is the soda ash. The Soda ash employed as thesaponifying agent may release carbon dioxide upon neutralization of the free fatty acid or upon saponifcation of the glyceride oils. This carbon dioxide evolved Within the coil 34 is of advantage in effecting vapori/'ration of the undesirable constituentsupon ldischarge of the Y the present process in which the soap stock from the refining operation and the saponiable matter are mixed in stream flow rather than being mixed within a tank as in Figure 1. Figure 2 merely shows the deviationof this processifrom that of Figure 1. Accordingly, the similar portions have been omitted and only the variation Water may be introduced-'in order to Y ieplbrefi'asthe .Senoriiiiabie material, or

,refining prQQeSS up to Iii iliseiii's in tien of themixture ry o ff 'the 'soap from the .i "mevl'iiisairieasiiiFigure 1- an, ttkgiseaarged dem the centrifuge mtdtaniilzsf This tenais preferneatingceu 60150 that the maybe heated up to such a condition be'purnpel." 'I 'his'ta'nk likewise con- @artisanat :ne

spo'nifirble Iiattr isupreferably'pre- Heatdfstiaris uSoap stock`arid saporiifiable 'matter vaf""vvithdr"lfvv'r`by means of Ipumps 53 and 64 respectivelyf rfI'liese pumpsAV may be driven by n'ileai'sfoalvariabl 4siineeliiotor r6,5. A variable sp'ed'driv frrelayb' interposed bctween'the two punipsws"tlit"the' proper`` proportion of soap stock and fatty matter may "be Vtv'ithdravvn Afrom the receptive tanks. These streams of soap stock and saponi'able matter may be lmixed with- 'in thniixerisrand frorn'it may be passed into the""hfeatin coil 34' Within the" chamber 35," as was the 'casein Fivgu'reN 1'5" In this manner ituis possible to'inlx the reactants instrearr'i flow as distinguishedfrom In''a'.'intaninggf a lsupply of the mixedireactants in a'tank asin Figure 1.

It is preferred ,to prelieat the saponiable `material ,to a degree atwhich substantial'saponication will take place immediately upon contact Withthe s'aponfying reagent.w When' fatty acids are the saponiabl'efmateri'al employed, itis preferred 'to prelieat ,tlirn to SucheJ temperature that they willriot ball up Aupon contact Fwith lthe saponifying' reagenti' 'Thus if the at'tyacids are p'rcheatcdto such aitemp'rature that the resultant soap iS molten no difficulty from ballirig up is' encountered. i

- In accordance with myprior patent referred to herein, 'other non-saponifyin alkalies such as alkali-.salts of alkali metals, for example, trisodiilm nbosohate, disiodium phosphate, sodium e qiiiyalent potassium salts; `alkalils; and amines such ne, etc., may in some part or all for the soda P 'iekfeui i 'iiiiilfiriiieiii ci veiiou's' 'of 'these non-saponifyiiig neutralizing agents may be employed in the present process. However, in view of the difficulty with which esterified-fatty acids such as glycerides and the like are saponied, higher temperatures and pressures maybe required in order to effect saponification. Y

In these cases it may be advisable to employ more saponiable material than is required to react with the excess alkali in the soap stock. In this event it is preferred to add suflicient caustic soda or potash to react with the excess saponiable matter. In this Way, as Was pointed out previously, the caustic alkali aids in the saponication of the esteried fatty acids. When free fatty acids are employed as the additional saponiable matter, relatively little diliiculty is encountered in effecting the reaction.

In the event the amines are used as the neutralizing or saponifying agent, it is preferred to omit the vacuum dehydration step as there is a tendency'for the amine soaps to decompose into the fatty `acid and amine, the latter" vaporizing at the low pressure in the vacuum chamber.

The various modifications Aof the process of the presentV invention areapplicalole'to vegetable and animal oils in general. Such vegetable oils as cottonseed oil, corn oil, soya beanA oi1,.1inseed oil, sesame oil, etc., arewithin the contemplationrof the invention. The term animal oils is also intended to include iish oils such as sardine, menliaden, or herring oils.l kBy the employment of the term saponiable matter in the yclaims I intend toinclude free fatty acidaglyceride oils, as well as other esters offatty acids either lWith mono-hydric or with poly-hydric alcoho1s. By the employment of the term foils or oil in the claims it is intended to include glyceride fats or oils. irrespective of the viscosity thereof.

vWhile I have disclosed thepreferred embodiments of my invention, it is understood that the details thereof may be varied Within the, scope of the following claims.Y n Y The process of purifying soap stockcontaining excess alkali froml the alkali reiiningj of glyceride oils and making soap therefrom, which comprises, adding saponiiiable material -to said soap stock to react with said excess alkali, heating the resulting mixture to a temperature sufficiently high to break down odoriferous substances contained therein and removing vaporizable materials from said soap stock inA vapor form to produce an improved soap from said soap stock..

2. The process of purifying soap stock containing water, excess alkali and odoriferous substances from the alkali rening of glyceride oils and making soap therefrom, which comprises, adding sufficient saponiable .material to said soap stock to react with said excess alkali, heating the resulting mixture to a temperature sufliciently high to break down said odoriferous 'substancesvand vaporizing water and otherv Vaporizable materials from vsaid soap.

3. The process of purifying soap stockcontainingexcess alkali from the alkali refining of glyceride oils and makingsoap therefrom, which comprises, adding sufficient saponifiable'material tosaid soap stock to react with said` excess alkali, continuously heating a stream of the resulting mixture to a temperature suliciently high to break down odoriferous substancesfcontained therein,discharging the resultingY heated stream into a vapor separating chamber and removing `ing excess alkali soap stock to react with said vaporizable materials` from the resultant soap in said chamber.

4. The process of purifying soap stock containing excess alkali from the alkali refining of glyceride oils and making soap therefrom, which comprises, adding suicient saponiable material to said soap stock to react with said excess alkali, heating a owing stream of said mixture under pressure and out of Contact with the atmosphere to a temperature suflciently high to break down odoriferous substances contained therein, discharging the resulting heated stream into a Vapor separating chamber and withdrawing vaporizable materials in vvapor form from said chamber at a rate suflicient to maintain a vacuum therein. Y

5. The process of purifying soap stock containing excess alkali from the alkali refining of glyceride oils and making soap therefrom, which comprises, adding saponifiable material to said Soap stock to react with said excess alkali, heating a flowing stream of the resulting mixture under pressure and out-of contact with the atmosphere'to a temperature suflicientlyhigh to break down odoriferous substances contained therein, discharging the resulting heated stream to a ValJOI separating chamber, withdrawing vaporizable materials from said chamber at a rate sufficient to maintain a vacuum therein, and continuously removing soap in molten anhydrous form from said chamber.rv

- .6. The process of purifying soap stock containfrom the alkali refining of glyceride oils and making soap therefrom, which comprises, adding saponiable material to said excessalkali, heating the resulting mixture during continuous movement thereof to a temperature sufliciently high to break clown odoriferous substances contained therein, and removing vaporizable materials from said soap stock as vapors to roduce an improved soap;

f7. The process of purifying soap stock containing excess alkali from the alkali l rening of glyceride oils and making` soap therefrom, which comprises, addingY saponiiable material to said soap stock to react With said excess alkali,`heating the resulting mixture to a temperature from 25o to 600 r'. ,and sufneienuy high to break down odoriferous substanceslcontained therein and removing vaporizable materials from said soap stock in vapor formto produce an improved soap.

'BENJAMIN CLAYTON. 

